Separating-machine.



No. 865,542. PATENTED SEPT. 10, 1907. F. STRINGHAM. SEPARATING MACHINE.

APPLICATION FILED N0v.7,19o5.

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PATENTED SEPT. 10, 1907.

F. STRINGHAM.. SEPAR'ATING MACHINE. APPLIOATION FILED Nov. 7, 1905.

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PATFT OFFICE.

FRED STRINGHAM, OF MANITOU, COLORADO.

SE PARATING-'VIACHINE v Specification of Letters Patent.

Patented Sept. 10, 1907.

Application filed November 7,1905. Serial No. 286,284.

To all whom it may concern:

Be it known that I, FRED STRINGHAM, a citizen of the United States,residing at Manitou, in the county of El Paso and State of Colorado,have invented certain new and useful Improvements inSeparating-Machines, of which the following is a specification.

My invention relates to a machine for treating mixed substances ofdifferent specific gravities in a Cemrninuted condition to separate thesubstances from each other, and relates more particularly to a machinefor treating metalliferous ores or' earths in order to separate theheavy or valuable from the lighter or base portions.

The rrrachine of my invention is of that class cornnronly termedorc-concentrators, and depends for its operation rrpon that propertywhich leads to the heavier or metallic portions of ore in a finelydivided condition settling to the bottom, and the lighter or earthyportions rising when the comminuted mass is agitated and worked Myprincipal object is to provide a machine which shall be simple andinexpensive in its construction and efficient in its operation, andwhich shall permit the concentration oi the ore to be carried on as acontinuous process, with a greater' degree of rapidity than has beenobtainable heretofore, and with a higher degree of recovery of thevalues or concentrates, This, generally speaking, l accomplish byconstructing the machine so that the sand, orI crushed and cornrninutedore is fed to the rotating concentrating receptacle of the machine atits center and bottom, and below the surface of the material undergoingconcentration, from which `point it is automatically fed and carriedoutwardly by the rotation of the receptacle and at the same time isworked and concentrated, the lighter waste portion being worked upwardlyby stirring mechanism preferably rotating in the opposite direction tothe direction of rotation of the receptacle, and finally being permittedto escape through openings or ports suitably arranged in the upperportion of the wall of the receptacle, while the concentrates or valuessettle and escape through openings in the bottom of the receptacle. I

The machine of my invention comprises various other features of novelty,among which may be mentioned the construction whereby the feed trrbeserves as shaft to cause the rotation of the stirring rneclranism, whilethe delivery tube acts as a shaft to cause' the rotation of theconcentrating receptacle or barrel, the adjustable arrangement of theopenings or ports through which the waste and the concentrates escape,whereby the degree of concentration may be regulated; the adjustablearrangement of the iced tube; the peculiar construction and dispositionof the stirring mechanism; and other novel features, which will bedescribed in the following specification and particularly pointed out inthe appended claims.

Referring to the drawings, Figure l is a front elevation, partiallybroken away and in section, oi a concentrating machine embodying thenovel features of my invention; Fig. 2 is a sectional plan view of themachine on line 2 2 of Fig. l., looking towards the top; and Fig. 3 isan elevation of the stirring mechanism on line 3 3 of Fig. 2.

Like parts in the several views are designated by the same referencecharacters.

The machine as illustrated, comprises a receptacle or barrel l withinwhich the concentration of the material to be treated is adapted to takeplace. This receptacle or barrel which may be of any convenient size andshape, and which may be constructed of any suitable material, as iron orwood, is provided preferably with several series of openings 3 in itsside walls, through which the lighter or waste material is allowed toescape. The several series are preferably arranged about the peripheryof the receptacle or barrel at different ydistances from the bottom, andare provided with means for opening and closing any particular series atwill, comprising, in the present instance, a ring or` band 4 encirclingeach series of openings and having in it holes 5 adapted to registerwith the openings in the wall of the barrel. Each band is arranged sothat it may be moved or rotated about the barrel to bring the openingsin it and in the barrel into or out of register, so that the size of thcpassage through them may be adjusted. Each band is valso provided withsuitable means, as a bolt (3 passing through its upturned ends, by meansof which it may be clamped in any position to which it is adjusted. Thebands are held against all movement excepting their rotary movement ofadjustment by the lugs 7 secured to the Wall of the barrel orreceptacle. As many series of openings as desired may be provided, vebeing shown in the present instance.

To permit the escape of the concentrates fr'om the barrel, a series ofopenings S is provided in the bottom of the barrel near its outer edge,for which an adjustable closure is provided in the form of a disk 9pivoted at the center of the bottom l() of the barrel and havingopenings l2 in its periphery corresponding with the openings S in thebottom of the barrel. A handle or lever i3 pivoted to the lug 14 securedto the outer wall of the barrel extends from the disk 9 into positionwhere it is accessible from the outside of the machine, and by means ofthis lever the disk may be rotated with respect to the bottom of thebarrel to bring the holes 8 and l2 into or out of register, to regulatethe size of the passage through them. Play between the lever 13 and disk9 A-s provided for by joining them through the medium of a pin and slotconnection 48, The collection of the values or concentrates, whichescape from the barrelby way oi the holes 8 in the bottom thereof isaccomplished, in the present instance, by providing an inverted-conicalor hopper-shaped part 15, which embraces and is rigidly secured to thebottom of the barrel, and which tapers to a hollow shaft 1G, firmlysecured to the hopper, as shown. The hollow shaft 1G, through which theconcentrates are conducted away, serves also as a medium through whichrotation is imparted to the barrel or receptacle 1, and to this end, isprovided with bearings, and a suitable connection with a source ofpower. The bearings, in the present instance, comprise the thrustbearing 17, one member of which is formed in a collar rigidly secured tothe hollow shaft 16, while the other member is supported on a suitableframework 18, and a lateral bearing 19, one member' of which is securedto the shaft while the other is mounted on a suitable support.

The mechanism for transmitting power to the shaft comprises, in thepresent instance, a bevel or miter gear consisting of a member 2Ocarried as a sleeve on the shaft 16, and a member 21 mounted on the endof a shaft 22 suitably supported in bearings 23 and adapted to receivepower from any convenient source by way of the pulley 24.

The novel mechanism which l have devised for conveying the material tobe concentrated to the barrel 1, comprises a feed pipe or tube 25preferably terminating at its upper end in a hopper 2G, into which thesand or comminuted material may be permitted to run, and with its lower'end extending into the center of the barrel or receptacle, andterminating at a short distance from the bottom thereof. 1n order torender adjustable the opening at the bottom of the feed tube 25,1preferably provide at the end of the tube an extension sleeve 39 adaptedto be moved longitudinally upon or within thc feed tube, and to beclamped in any position to which it has been adjusted. This 1 accomplishin the present instance, by providing longitudinal slots 27 at the endof the feed tube 25, in which clamping bolts 28 are adapted to slide.

The concentration of the sand or comminuted material delivered to thebarrel through the feed pipe 25 is accomplished through the medium ofworking and concentrating mechanism which comprises, in the presentinstance, a number of forks or groups of stirring rods adapted to movein the annular space between the feed tube and the inner wall of thebarrel, and to stir and work the material. lt will be obvious that asmany of these stirring forks as desired may be employed. In the presentmachine, 1 have shown eight arranged at equal distances from each otherwithin the barrel, and supported from a disk 3() which extends over andserves as a cover for the barrel, but which is not secured thereto.

1 have found it desirable to give the stirring forks or rods a movementof rotation in the opposite direction from that of the barrel, and as aconvenient means to that end l rigidly secure the disk or cover 30, towhich they are attached, to the feedY tube 25, as shown, and arrange thetube so that it serves also as a shaft for the transmission of power toeffect the rotary movement of the forks. lt will, of course, beunderstood that the movement of rotation may be imparted to the forks inother manners than through the medium of the cover of the barrel and thefeed pipe, without departing from the spirit of my invention. 1 find itconvenient, however, to employ the particular construction illustrated,which consists, in addition to securing the stirring forks to themovable cover of the barrel and it to the feed tube 25, in arrangingsaid tube for rotation by providing it with end and Cross thrustbearings 31 and 32, respectively, one member of each of which is securedto the feed tube, while the other is arranged upon a suitable support33, and in providing it with a miter or bevel gear, one of the members34 of which is secured as a collar on the feed tube, while the other iscarried on the end of a suitably supported shaft 35, the other end ofthe shaft being in communication through the medium of the pulley 3Gwith a suitable source of power.

As heretofore stated, the stirring forks in the present instance areeight in number, and are indicated by the reference numerals 38, 39, 40,41, 42, 43, 44 and 45. Each of these forks comprises ahead orcross-piece having a centrally located stein 29 securing it to the topof the barrel, and a number of stirring rods or tines de-y pending fromthe head. l have found that six tines is a convenient number to employin connection with each fork, and l have also found that a higher degreeof concentration can be secured when the tines are varied in length andin shape. ln the present instance, as illustrated, the forks 3S and 42are each provided with six flat blunt ended tines, which may extend towithin say one inch of the bottom of the barrel. The forks 45 and 41each have six tines, the inner tine of each fork being flat, while thefive remaining tines are preferably round in cross-section and pointedas shown in Fig. 3. As illustrated, the tines of these forks extend asclosely as possible to the bottom of the barrel, the separation beingjust sufficient to insure clearance. The forks 44 and 40 are eachprovided with six flat tines similar to the tines of the forks 38 and42, excepting that they do not extend quite so near to the bottom of thebarrel, the separation being, say, two inches instead of one inch.

The forks 43'and 39 are each provided with six tines, one flat and theothers round and pointed, the arrangement being the same as in forks 45and 41. By this arrangement the flat and blunt tined forks alternatewith the round and sharp tined forks, the fiat tines serving to work andraise the lighter or base portions of the sand in the upper part of thebarrel, while the round sharp tines work the bottom layer ofconcentrates without raising any of the values into the upper portion ofthe barrel where they maybe mixed with the waste and lost.

l find that at times it is advantageous to turn the fiat tines of theforks about their longitudinal axes so that their surfaces may beinclined instead of flat with respect to their direction of rotationabout the barrel, and to this'end l mount them in their crossheads sothat their angle may read-ily be varied. Thus, for instance, the outer`five teeth of forks 40 and 44 may be inclined, so that in encounteringthe sand they will throw it towards the centerof the barrel, while thetines of forks 38 and 42 may be arranged to throw the sand towards thecircumference of the barrel in order` more thoroughly to agitate andwork it. Or, if desired, the angle of all of the teeth may be adjustedso as to cause them to throw the sand which they encounter eithertowards the circumference of the barrel, as in working wet, slimy sand,or toward the feed tube, as in working dry sand, where it is desirableto partially counteract the centrifugal force of rotation. lt will beobserved that the tine of each fork nearest the feed tube 25 is flat andis allowed to extend straight down, and thatthe face of each of thesetines is arranged at right angles to its direction of movement, althoughits angle may, if desired, be

varied, as in the case of the outer tines.

lhe operation of the machine is as follows: The sand or material to beconcentrated is fed into the hopper26 and is conducted by it to the feedtube 25, through which it falls to the bottom of the concentratingbarrel or receptacle l. When the extension sleeve 2G at the bottom ofthe feed tube is adjusted to allow the proper opening between the tubeand the bottom of the barrel, the sand is held at the bottom of thetube, and does not flow to any considerable extent into the barrel. Assoon as the barrel is caused to rotate, however, the centrifugal forcewhich is imparted to the sand at the bottom of the feed pipe causes itto spread out over the bottom of the barrel, whereupon more sand is fedthrough vthe tube 25 to take its place, and so long as the material issupplied the feed is automatic and continuous. As the sand flows fromthe bottom of the tube it is encountered by the tines of the stirringforks moving in the opposite direction, which stir and work it, thesharp tines working the lower layer of the material while the flat tineswork the upper portions, the lighter or waste portions movingcontinuously upward, while the values or concentrates move down. By thetime the sand is moved to the periphery of the barrel or receptacle itsconstituents are thoroughly separated, and finally escape, the wastethrough the holes 3, and the concentrates through the holes 8. Theconcentrates fall into the hopper 15, down which they slide into thehollow shaft 16 and through it to their point of delivery. The wasteportions, after escaping through the openings 3, may be led away in anysuitable manner, or may be merely allowed to fall in a heap which may beremoved from time to time.

The degree of concentration of the sand may be regulated to a nicety bymeans of the adjustable closures 4 of the openings 3 in the side wall,and the closure 9 ofthe openings S in the bottom of the barrel. Byopening all of the series of openings in the side of the barrel theamount of working that the sand receives and the degree of concentrationwill be comparatively slight. As one after the other of the lower seriesof openings is closed, the depth of the sand in the barrel and theamount that it is worked increases, and when all are closed exceptingthe upper series, the maximum degree of concentration will be effected.Moreover, by adjusting the size of the passages S from the bottom of thebarrel by means of the adjustable disk 9 the rate at which theconcentrates are permitted to escape may be regulated to still furtherincrease the amount of working which the sand in the barrel is adaptedto receive before it is permitted to escape.

lt will be seen that by virtue of the novel construction which 1 employ,the feed is entirely independent of the height of the sand in thebarrel,the level of the sand undergoing concentration being, in practice,sometimes as much as a foot above the point at which the sand isdelivered into the barrel. The delivery of the sand to the bottom andcenter of the concentrating receptacle not only results in all the sandreceiving a uniform treatment, but also in its being exposed to theaction of the working and concentrating mechanism for the maximum lengthof time, while it is moving upwards and outwards to the ports where itfinally escapes from the machine. Moreover, the rapid movement of theteeth of the stirring mechanism through the sand results in a scouringaction which assists in freeing the metallic particles, as of rustygold, from the particles of quartz to which they are attached. It willalso be seen that my machine is equally well adapted to treat materialeither in the wet or dry condition.

I claim:

1. Inr an ore-concentrator, the combination with a barrel or receptacleand means for rotating the same, o1' a feed tube extending; to within ashortdistance of the bottom of said barrel at the center thereof, aplurality of stirring arms `extending from the top of said barrel, andmeans for moving said arms to work and separate the ore, said barrelhaving a series of openings in the bottom to permit the passage of theconcentrates, and another series disposed circumferentially about theside through which the waste material is adapted to escape.

2. In an ore concentrator, the combination of a barrel or receptaclearranged to continuously discharge the heavier material by gravity andadapted to receive the material to be treated, a rotatable feed tubeextending axially of said barrel to within a short distance of thebottom thereof to permit the material to automatically feed into thebarrel according to the rate of discharge therefrom, a series ofstirring arms mounted upon and carried by said feed tube and adapted towork the material in the barrel, and means for rotating the barrel andfeed tube.

In an ore concentrator, the combination with a concent1-ating disk orplatform adapted for rotation and arranged to continuously discharge theheavier material by gravity, of a feed tube extending axially of saiddisk from a source' of supply of material to be concentrated to a shortdistance from the surface of said disk or platform, means for rotatingsaid disk to cause the material to flow from the mouth of said tube, andstirring arms adapted to work and concentrate the material carried onsaid disk.

4. In an ore-concentrator, the combination with a barrel adapted forrotation, of a feed tube extending axially of said barrel to Within ashort distance from the bottom thereof, a series of arms or forksextending into said barrel and adapted to rotate around` said feed pipeto work and concentrate the material delivered thereby, and means forimparting a relative movement of rotation to said stirring arms and saidbarrel, said arms or forks being inclined forwardly in the direction ofrotation.

5. In a concentratingmachine, the combination, with a receptacle for thematerial to be concentrated and arranged to continuously discharge theheavier material by gravity, of a feed tube extending centrally of saidreceptacle to within a short distance of the bottom thereof and adaptedto supply the material thereto, stirring arms located in said receptaclebetween the feed tube and the walls of said receptacle and arranged towork the material outwardly and upwardly, and means for rotating thereceptacle and stirring arms in opposite directions.

6. In an ore concentrator, the combination of a rotatable receptacle forthe material to be concentrated, said receptacle being provided with aplurality of series of openings, one series being arranged in the bottomof the receptacle for the continuous discharge of the heavier materialor concentrates by gravity and the other series in the sides of thereceptacle for the discharge or escape of the lighter or waste material,and a rotatable feed tube extending centrally of the receptacle forfeeding the material thereto, and means operated by the feed tube forworking the waste material toward the last mentioned series of openingsand the concentrates toward the first mentioned sei-ies of open- 7. Inan ore-concentrator, the combination with a barrel for the material tobe concentrated, of a rotatable feed tube extending axially of saidbarrel to within a short distance of its bottom, a series of forksconnected with said feed tube and extending down into said barrel, saidbarrel having openings therein to allow the separate escape of theconcentrates and the waste material, and means for causing said feedtube and said'barrel to rotate at different rates, whereby the materialows out of the feed tube into the barrel and is there worked andconcentrated by said forks. v

8. In an ore-concentrator, the combination with a rotatable receptacleadapted to receive the material to be concentrated and arranged tocontinuously discharge the heavier material by gravity, of means forfeeding the material to said receptacle, means for working andconcentrating the material within said receptacle, said reccp taclebeing provided with a series of circumferentially disposed openings inthe walls thereof, and means for adjusting the size of said openings,whereby the degree of concentration may be regulated.

9. In an ore-concentrator, the combination with a bar -rel for thematerial to be concentrated, of means for supplying the material to thebottom of the barrel and approximately at the center thereof, and forksadapted to rotate within said barrel and axially of the same to work andconcentrate the material therein, certain of said forks being providedwith tines having blunt ends and others being provided with tines havingsharp pointed ends, the blunt ended tines terminating at some distancefrom the bottom of said barrel, and being adapted to work the upperportions of the material, and the sharp pointed tines just clearing thebottom of the barrel and being adapted to work the lower layer of thematerial.

10. In an ore-concentrator` the combination with a re ceptacle adaptedto receive the material to be concentrated and arranged to continuouslydischarge the heavier material by gravity, of means for delivering saidmaterial to the bottom of said receptacle at approximately the centerthereof, said receptacle being provided with lower and upper openingsadapted to permit the independent escape therefrom of the concentratesand of the waste material, means for rotating said receptacle to cause amovement of the material from the center to the periphery of saidreceptacle, and stirring arms for working the material and causing anupward movement of the waste portion thereof during the aforesaidoutward movement.

11. In an ore-concentrator, the combination with a rotatable receptacleadapted to receive the material to be concentrated and arranged tocontinuously discharge the heavier material by gravity, of means forfeeding the material to said receptacle, means for working andconcentrating the material within said receptacle, said receptaclehaving a plurality of series of openings arranged circumferentially atvarying distances from the bottom of the receptacle, and means foropening or closing at will any one or more of said series of openings,whereby the degree of concentration may be regulated.

12. In an ore-concentrator, the combination with a concentrating barrel,of a feed pipe extending axially of said barrel to within a shortdistance of the bottom thereof, a series of forks adapted to stir thematerial within said barrel, a series of openings in the wall of saidbarrel adapted to permit the escape of the waste material, otheropenings in the bottom of the barrel near the periphery thereof topermit the escape of the concentrates, a disk rotatably secured to thebottom of the barrel and having holes therein registering with theopenings in the bottom of the barrel, whereby the extent of saidopenings may be regulated by turning said disk, and means for relativelyrotating said barrel and stirring forks to concentrate the material inthe barrel.

13. In an ore-concentrator, the combination with a barrel or receptacleadapted to receive the material to be concentrated and arranged tocontinuously discharge the heavier material by gravity, of means forsupplying the material to the bottom of the barrel at approximately thecenter thereof, and forks adapted to rotate withinsad barrel and axiallyof the same to work and concentrate the material therein, the tines ofone of said forks being arranged to extend closer to the bottom of thebarrel than the tines of another fork. i

14. In an ore-concentrator, the combination with a barrel or receptaclefor the material to be concentrated, of means for continuously supplyingthe material to the bar rel, means acting within the barrel to work andconcentrate the material, said barrel being provided with a series ofsubstantially equal apertures in substantially the same horizontal planeabout the circumference thereof for the escape of the waste material,and means for simultaneously opening or closing all of said apertures tothe same degree, whereby the escape of the waste material is evenlydistributed about the circumference of the barrel.

15. In an ore-concentrator, the combination with a rotatable barrel orreceptacle for the material to be concentrated, said barrel beingprovided with openings therein to permit the independent escape of theconcentrates and the waste material, of a feed tube extending axiallyinto the barrel and adapted to convey the material to be concentrated tothe center of the bottom of the barrel, a top or cover for the barrelrigidly secured to said pipe, stirring arms secured to said cover or topand extending into the barrel, and means for causing a relative rotationof said feed pipe with its associated stirring arms and said barrel.

16. In an ore-concentrator, the combination with a barrel or receptacleadapted to receive the material to be c0ncentrated and arranged tocontinuously discharge the heavier material by gravity, said receptaclehaving openings in the periphery of the bottom thereof to permit theescape of the concentrates, of means for feeding the material to beconcentrated tol said receptacle, stirring arms or forks extending intosaid receptacle and adapted to work and concentrate the materialtherein, a delivery tube extending axially from the bottom of thereceptacle and rigidly secured thereto, and adapted to support thereceptacle, said delivery tube being in communication with the openingsfrom said receptacle for permitting the passage of the concentrates, andmeans for effecting rotation of said delivery tube to rotate thereceptacle and thereby effect the concentration of the material therein.

1T. In an oreconcentrator, the combination with a barrel or receptacleadapted to receive the material to be concentrated and arranged tocontinuously discharge the heavier material by gravity, said receptaclebeing pro vided with openings for the independent passage therefrom ofthe concentrates and the waste material, a feed tube extending axiallyinto said receptacle to within a short distance of the bottom thereof,stirring arms connected with said tube and extending into thereceptacle, a delivery tube extending axially from the barrel andrigidly connected with the bottom thereof, said delivery tube being incommunication with the openings for permitting the escape of theconcentrates, and means adapted independently to rotate the feed tubewith its associated stirring arms, and the delivery tube with itsassociated receptacle.

18. In an ore-concentrator, the combination with a barrel or receptacleadapted to receive the material to be concentrated and arranged tocontinuously discharge the heavier material by gravity, said barrelbeing provided with openings therein to permit the independent escape ofthe concentrates and the waste material, of a feed tube extendingaxially into the barrel to a short distance from the bottom thereof,stirring arms connected with sa-id feed tube and extending into thebarrel, and means for causing the independent rotation of said feed pipewith its con nected stirring arms and said barrel.

10. In an oreconcentrator, the combination with a receptacle for thematerial to be concentrated, of means for effecting the rotation of saidreceptacle, a feed tube extending to within a short distance of thecenter of rotation of the receptacle, stirring forks provided withflatfaced tines adapted to be turned about their longitudinal axes tovary the engaging angle of the tine faces, and means for adjusting theseparation between the feed tube and the receptacle, whereby therapidity of feed may be regulated.

20. In an ore-concentrator, the combination with a barrel or receptacleadapted lto receive the material to be concentrated and arranged tocontinuously discharge the heavier material by gravity, said barrelbeing provided with openings therein to permit the independent escape ofthe concentrates and the waste material, of a feed tube extendingaxially into the barrel, an adjustable extension sleeve on the end ofsaid feed tube, whereby the opening between the end of the feed tube andthe bottom 'of the receptacle may be regulated, means for regulating therate of escape of the concentrates, and means for causing the rotationof said receptacle or barrel.

2l. In an ore-concentrator, the combination with a rotatable barrel orreceptacle adapted to receive the material to be concentrated andarranged to continuously discharge the heavier material by gravity, of arotatable feed tube for continuously supplying the material to thebottom of the receptacle at approximately the center thereof, and toi-kssecured to said tube and adapted to rotate within in a directionopposite to that of said receptacle and axially of the same to work andconcentrate the material therein, said forks being provided with flatfaced and blunt-ended tines adapted to be turned about theirlongitudinal axes, whereby the engaging angle ot' the faces of the tinesmay be varied, and with a series of sharp-pointed tines alter natingwith said other tines.

22. In an ore-concentrator, the combination with a rota* table barrel orreceptacle adapted to receive the material to be concentrated andarranged to continuously discharge the heavier material by gravity, ofmeans for continuously supplying the material to the bottom of thereceptacle at approximately the center thereof, and forks adapted torotate Within in a direction opposite to that of said barrel and axiallyof the same to work and concentrate the material therein, said forksbeing provided with at-faced, blunt-ended tines and also with sharppointed tines just clearing the bottom of the barrel and adapted to Workthe lower layer of material without raising the values therein into theupper portion of the material.

23. In an ore concentrator, the combination of a rotatable barrel orreceptacle for the material to be concentrated and having means fordischarging the heavier material by gravity, means for supplying thematerial to the barrel or receptacle consisting otl a central feed tubeextending therein to within a short distance of the bottom, and theseries of stirring devices operating Within and rotating in a directionopposite that of said barrel or receptacle and comprising arms or tinesof different construction and length, some of said arms extending closerto the bottom than others and some of the arms being shaped or formeddifferent from the others, and arranged in alternating series, for theproper treatment of the waste material and the concentrates.

FRED STRINGHAM.

Witnesses z JAY B. MERRITT, L. SUMNER, J. R. MCQUILCLON.

